We've been long overdue for a tree post (nearly a month has gone by). I've been waiting on this one. The thought of trying to sort out maples and oaks filled me with quite a bit of trepidation. I've lost sleep over it. Mostly because, before I started researching this post, all maples and all oaks pretty much looked the same to me.
I think we've got a handle on this now. Tree people use several methods for identifying trees: examining the buds, the bark, the fruit. I usually look at the leaves, which has proved a successful strategy so far. God help me when I start doing elms.
However, that brings me to the question, completely gratuitous, but something I think everyone should know:
What Is a Leaf?
In the picture below, how many leaves can you count below my finger?
In most leaves, the petiole (stem) attaches to the branch and supports the lamina (blade). In the axil (the spot where the petiole attaches to the branch), you'll find a bud. A bud is a bundle of meristematic tissue that can, if it gets good grades and eats its vegetables, grow up to be a branch.
Look at this picture. See the buds at the spot where the leaf attaches to the branch? Everything past the bud is a leaf.
So, the answer to the question about the first picture? One leaf. I'm pointing at the bud with my finger. All the leaflets below my finger are part of one leaf.
Let me get technical. Most tree leaves grow in two basic ways. In pinnate leaves, the veins extend from one major, central vein, like teeth on a comb. In palmate leaves, multiple major veins radiate from a central point, where the lamina (blade) attaches to the petiole (stem), like a starfish. Simple leaves have a single blade that covers all the veins. Compound leaves divide into unconnected leaflets that grow around each vein.
So, go back. The first picture shows a compound pinnate leaf. In the second, you see a simple pinnate leaf. Remember the Horsechestnut leaf from an earlier post? Compound palmate.
Not all leaves look like leaves. Needles on conifers, spines on cacti, and the red part of poinsettias are all leaves.
Maple vs. Oak
How do you tell an Oak and a Maple apart? I wanted to know because the two most common trees you see here are maples and oaks. The two most common angiosperms, that is. Remember when we said conifers are gymnosperms and that means "naked seed?" Angio comes from Greek and means vessel. An angiogram is an x-ray of blood vessels. Angiosperm means a seed that comes inside a vessel, namely fruit. Gymnosperms, on the other hand, spit their seeds out willy nilly all over the ground like a child eating watermelon.
And to answer the age old question: You call anything with seeds a fruit. You call any other part of the plant (leaves, stems, roots) a vegetable. The word vegetable comes from Old French. Originally, the word meant any living plant. Sometime during the 1700s, the word took on the meaning we use today, more specifically, and edible herb or root. So that's that.
And that's completely off topic.
Maples and oaks. Maples have simple palmate leaves:
Oaks have simple pinnate leaves:
They don't look so simple because the deep cuts between the veins form lobes. The lobes connect before they reach the major vein or stem and so they aren't compound leaves.
The fruit also looks completely different. Maples produce a dry, winged fruit called a samara; you probably played with these as a kid:
Oaks produce acorns. Everyone knows the acorn. If you've never had one thrown at you, well, you haven't really lived:
Maples
Most maples look very similar from a distance. Woodworkers use wood from each of them and classify them as hard maples or soft maples, depending on the type of wood they have. All maples have sugary sap used to make maple syrup.
The Sugar Maple (Acer saccharum) is your classic maple with the easiest leaf to spot. The Canadians use this leaf for their national flag and they use this tree as their primary source of maple syrup. Canadians pump out 80% of the world's maple syrup (7 million gallons a year) and they speak French while doing it. All but a tiny fraction of Canada's maple syrup comes from Quebec. Sugar maples also have the hardest, densest wood of all maples. If you've ever gone bowling, you've rolled your ball down a maple wood lane.
How you know it's a Sugar Maple:
- Three major lobes, somewhat pointed
- Shallow cuts between lobes
- Very small fourth and fifth lobes
- Light green in color
- Shaggy bark
The Sugar Maple and the Silver Maple (Acer Saccharinum) are the two most common maples here in Illinois. Unlike the Sugar Maple, the Silver Maple has soft, brittle wood used for small ornamental doodads. Silver Maple buds form the largest portion of the Eastern Gray Squirrel diet.
How you know it's not a Sugar Maple:
- Narrower, more distinct lobes
- Sharp angles between lobes
- Underside of leaf looks silvery green
The Black Maple (Acer nigrum) also has hard wood, mostly used for basketball courts and cutting boards. I found a young tree, with dark, gray bark. As the tree ages, the bark grows darker, turning almost black in old trees. Hence the name.
How you know it's not a Sugar Maple:
- The three major lobes are narrower and longer
- Lobes come to a sharp point
- Leaves always have a wilted look
- Dark bark
You don't see as many specimens of the nefarious Norway Maple (Acer platanoides). This Old World tree has become an invasive species in North America. The tree releases a chemical into the soil that kills undergrowth. Urban planners really liked them in the 60s and 70s before we realized how much they suck. New Hampshire banned this tree completely and Meijer's no longer sells it. Meijer's (pronounced like Oscar Mayer) comes from Michigan and has over 200 stores throughout the Midwest. It's basically the same thing as Wal-Mart, only the employees wear red instead of blue.
How you know it's not a Sugar Maple:
- Darker leaves
- Three major lobes point in same direction
- Three major lobes nearly the same length
- More pronounced fourth and fifth lobes
- Bark with tight, criss-crossing pattern
The Red Maple (Acer rubrum) isn't as common either. Another soft maple, the Red has bark that shrinks considerably during drying and burns easily when being machined. My suggestion: Do Not Buy. Rhode Islanders liked the Red so much, they named it their state tree. Also, don't let your horses eat the leaves. It makes their blood cells explode. I'm not even kidding.
How you know it's not a Sugar Maple:
- Only three narrow lobes
- Supposed to be the best Maple for fall colors
The Amur Maple (Acer ginnala). This is my Holy Grail of maples. Supposedly, these can be found in Illinois, but I haven't seen one yet. That's why I don't have a picture. Like the Norway, the Amur is invasive, but it's from Siberia and Mongolia. It's usually smaller than other maples as well, more like the Japanese Maple (Acer palmatum). I'll post one as soon as I find it.
Oaks
Compared to oaks, maples are pretty easy to distinguish. I'm still figuring out oaks. Most Oaks grown in North America fall into one of two groups, the White Oak group and the Red Oak group. White Oaks have rounded lobes and include Whites, Chinquapins, Swamp Whites, Live Oaks, and Bur Oaks. Red Oaks have pointed lobes and include Reds, Blacks, Pins, and Scarletts.
The State Tree of Illinois, the White Oak (Quercus alba), has a unique wood that resists both moisture and rot. The oak barrels used to age wine and whiskey come from White Oaks. The builders of the USS Constitution (remember the Eastern White Pine masts?) used White Oak planks for the hull. A variety of wildlife, including our Eastern Gray Squirrel, eat the acorns of the White Oak. Native Americans did too. In the interest of full disclosure, Connecticut and Maryland also claim this tree as their own.
In Illinois, you can call any oak a White Oak and have an 80% chance of getting it right. However, if you want to be extra sure, count the lobes. White Oaks have seven:
The Red Oak (Quercus rubra) is one of the most important timber trees in North America. Woodworkers use this tree for flooring, trim, and furniture. I read that the grain is so open, you can blow smoke through a freshly cut board. Don't get it wet. Also, New Jerseyans call this their state tree.
And of course, we have the Swamp White Oak (Quercus bicolor). The leaves have shallow lobes. Contractors use this often as a landscaping tree. Swamp White Oaks have a wide variety of color in the autumn and can grow up to 60 feet tall.
The Parting Shot
Planners of the September 11 Memorial Plaza in New York chose Swamp White Oaks for their size, variety, and color. They planted over 400 of them around the two reflecting pools located in the footprints of the original towers.
(I didn't take this picture. It's from Wikimedia.)
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